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1.
J Vet Intern Med ; 26(4): 1056-60, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22686408

RESUMEN

BACKGROUND: The association between plasma cardiac troponin I (cTnI) and the magnitude of cardiac enlargement in calves with congenital heart disease (CHD) are not well defined. OBJECTIVE: To investigate the relationship between plasma cTnI concentrations and cardiac size in healthy calves and calves with CHD. ANIMALS: A total of 19 healthy calves (control) and 12 Holstein calves with CHD (patent ductus arteriosus, ventricular septal defect, tetralogy of Fallot or double outlet right ventricle). METHODS: Case control study. All animals underwent a comprehensive transthoracic echocardiographic study to document cardiac health or presence of CHD. The vertebral heart score (VHS) was determined in each animal using right lateral survey radiographic images. Blood samples were collected via jugular venipuncture and plasma cTnI concentration and creatine kinase (CK) activity were determined by a 3rd generation immunoassay and an automatic biochemical analyzer, respectively. Groups were compared using Mann-Whitney U-test and receiver-operating characteristics (ROC) curve analysis. RESULTS: Calves with CHD had significantly larger VHS values and higher plasma cTnI concentrations (P < .001) compared to control. Creatine kinase activity was not different between the control and CHD groups of calves. Diagnostic cutoffs of VHS and plasma cTnI for discrimination of groups were 8.9 vertebrae and 0.035 ng/mL, respectively. The cTnI concentration in plasma was significantly correlated with VHS (r (2) =0.512, P < .001). CONCLUSION AND CLINICAL RELEVANCE: Our results suggest that determination of plasma cTnI concentrations in calves with clinical signs compatible with CHD might prove useful as a guide to quantify cardiac remodeling associated with increased cardiac size.


Asunto(s)
Enfermedades de los Bovinos/sangre , Cardiopatías Congénitas/veterinaria , Troponina I/sangre , Animales , Estudios de Casos y Controles , Bovinos , Enfermedades de los Bovinos/diagnóstico por imagen , Enfermedades de los Bovinos/patología , Ecocardiografía/veterinaria , Cardiopatías Congénitas/sangre , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/patología , Tamaño de los Órganos/fisiología , Curva ROC , Radiografía
2.
Am J Physiol ; 262(4 Pt 1): G732-9, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1348908

RESUMEN

Actions of human calcitonin-gene related peptide (hCGRP) on acetylcholine (ACh) discharge and gastrin and somatostatin release from rat antral mucosal-submucosal fragments were examined in both dynamic perifusion experiments and short-term static incubation studies. The principal findings of the dynamic perifusion experiments were that hCGRP exerted a dual or biphasic effect on ACh discharge and gastrin release. Initial exposure of antral tissues to hCGRP (1 x 10(-8) M) resulted in stimulation of both ACh and gastrin release that was of brief duration. Continued hCGRP perifusion caused subsequent inhibition of ACh and gastrin release that was substantially greater in duration and magnitude than the initial stimulatory responses. Static incubation studies indicated that hCGRP (10(-10) to 10(-7) M) stimulated somatostatin and inhibited gastrin release in a dose-dependent manner. Inhibition of gastrin and ACh release by hCGRP appeared to be an indirect effect that was mediated by somatostatin as suggested by studies with pertussis toxin (200 ng/ml). Furthermore, studies with atropine (1 x 10(-6) M) and tetrodotoxin (1 x 10(-6) M) indicated that CGRP-induced stimulation of somatostatin release and inhibition of ACh discharge occurred independent of muscarinic receptor activation and nerve excitation. In conclusion, results of these studies indicate that CGRP is capable of exerting both stimulatory and inhibitory effects on ACh release from mucosal-submucosal neurons and gastrin release from antral mucosal G cells in in vitro studies. These data suggest that the inhibitory effects of CGRP on cholinergic discharge and gastrin release are due to the paracrine effects of somatostatin released from antral D cells by direct action of CGRP.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/farmacología , Glándulas Endocrinas/citología , Neuronas/fisiología , Sistema Nervioso Parasimpático/citología , Antro Pilórico/citología , Acetilcolina/metabolismo , Animales , Atropina/farmacología , Gastrinas/metabolismo , Neuronas/efectos de los fármacos , Perfusión , Toxina del Pertussis , Somatostatina/metabolismo , Tetrodotoxina/farmacología , Factores de Virulencia de Bordetella/farmacología
4.
Gastroenterology ; 101(5): 1178-86, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1936787

RESUMEN

gamma-Aminobutyric acid, a neurotransmitter in the central nervous system, has been shown to be present in and synthesized and secreted by rodent and feline myenteric plexus neurons. The aims of the present studies were to measure gamma-aminobutyric acid concentrations and synthesis and to establish cellular localization and uptake of gamma-aminobutyric acid by immunocytochemistry and autoradiography, respectively, within mucosal and submucosal tissues of the rat antrum. Direct demonstration of [3H]gamma-aminobutyric acid release and the effects of exogenous gamma-aminobutyric acid and muscimol, a GABA alpha agonist, on [3H]acetylcholine release from antral mucosal/submucosal fragments were examined in perifusion experiments. gamma-Aminobutyric acid content and synthesis, as reflected by glutamic acid decarboxylase activity, were present within antral mucosa at levels two to three times that of the body and muscular layers of both the gastric body and antrum. gamma-Aminobutyric acid was identified immunocytochemically, principally in mucosal epithelial cells of the antrum. Exogenous gamma-aminobutyric acid and muscimol were capable of stimulating acetylcholine release through a GABA alpha receptor-mediated mechanism that was abolished by tetrodotoxin. These results indicate that gamma-aminobutyric acid is present in and taken up by epithelial cells of the gastric antrum and that gamma-aminobutyric acid is capable of being synthesized by antral mucosal/submucosal tissues. Furthermore, these studies suggest that a peripheral gamma-aminobutyric acid mechanism that may modulate cholinergic neurotransmission and endocrine cell function exists within the antrum.


Asunto(s)
Mucosa Gástrica/metabolismo , Antro Pilórico/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Acetilcolina/metabolismo , Animales , Autorradiografía , Sistema Digestivo/química , Células Epiteliales , Epitelio/química , Mucosa Gástrica/química , Mucosa Gástrica/citología , Glutamato Descarboxilasa/metabolismo , Inmunohistoquímica , Técnicas In Vitro , Mucosa Intestinal/química , Masculino , Muscimol/farmacología , Antro Pilórico/química , Antro Pilórico/citología , Ratas , Ratas Endogámicas , Ácido gamma-Aminobutírico/análisis , Ácido gamma-Aminobutírico/biosíntesis
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